Molecular analysis of adrenergic receptor genes and interleukin-4/interleukin-4 receptor genes in patients with interstitial cystitis.

Abstract

Interstitial cystitis is a chronic and sterile inflammatory disease of the bladder. Clinically many patients with interstitial cystitis also have allergic or autoimmune diseases. Recent studies have suggested that allelic variations in the adrenergic receptor beta2 gene, the interleukin (IL)-4 gene and its receptor gene are closely associated with immune diseases. Therefore, we studied adrenergic receptor genes alpha1d (ADRA1d), beta2 (ADRB2) and beta3 (ADRB3), and IL-4/IL-4 receptor genes in patients with interstitial cystitis. We studied 55 patients with interstitial cystitis and 228 controls. Genomic DNA was extracted from a whole blood sample collected from each subject. We analyzed 5 gene polymorphisms (G404781T, Arg16Gly, Trp64Arg, C589T and Ile50Val) per gene (ADRA1d, ADRB2, ADRB3, IL-4 and IL-4 receptor, respectively) and their relationship to interstitial cystitis. The frequency of the Arg/Arg genotype of the ADRB2 gene and the TT genotype of the IL-4 gene were significantly higher in patients with interstitial cystitis than in controls. A significant difference of ADRA1d genotype prevalence was also observed. However, there were no remarkable differences of IL-4 receptor or ADRB3 genotype prevalences. Variants of the ADRB2, ADRA1d and IL-4 genes may be related to a predisposition to interstitial cystitis.